This invention relates to a monitor control apparatus and a monitor control program for a communication network, and more particularly, to a bandwidth management method for a packet transport network that can support various services and protocols on the same infrastructure.
A conventional network constitutes a physical network for each protocol.
Recently, a transfer network accommodating various client protocols has been required for shifting to the next-generation network providing various services.
As a method for accommodating various kinds of client protocols, a method called Multi-Protocol Label Switching (MPLS) in which an identifier called a label is added to a frame or packet and then the frame or packet is transferred has been attracting attention.
By combining the above-mentioned MPLS method, a circuit emulation technology, and an operations, administration, and maintenance (OAM) technology, it is possible to realize a packet transport network in which a plurality of types of interfaces (Synchronous Digital Hierarchy (SDH), Ethernet, etc.) can be implemented between nodes and a plurality of types of paths (virtual container (VC) path, Ethernet path, etc.) can be accommodated in the same fiber.
When a network is operated, a network monitor control apparatus is required to be provided with a function of searching for a path route that can be opened.
As a conventional route calculation method, there is a route calculation method in which the total cost of links on a route is calculated and a route whose total value is the smallest or the largest is selected.
As a typical example of such route calculation method, Dijkstra's algorithm is used.
In this route calculation method, for example, a physical bandwidth on the link is represented as the cost of link and the route whose total value of the cost of the links on the route is the largest or the smallest is calculated, to thereby calculate the route in which more packet communication traffic can be accommodated.
In the case of this route calculation method, only the total value of the cost of the links on the route is taken into consideration, and hence when the cost of one link is extremely small or large, there arises such a problem that the one link becomes a bottleneck and the traffic is interrupted.
In view of the above, an improved method for Dijkstra's algorithm has been studied in which not only the total value of cost of the links on the route but also the size of cost of each link on the route is taken into consideration, to thereby solve the problem (Japanese Patent Application Laid-open No. 2001-244974).
Further, as another route calculation method in which other conditions on the link, transferred packets, and the like are taken into consideration, the following method has been studied.
Specifically, in this method, while managing the connection state of nodes in the network, referring to such information, calculation is performed by a method similar to the Dijkstra's method on routes starting from a start node to an end node to acquire a plurality of route candidates. Then, a cost check for judging whether or not a route is available is performed on the calculated route candidates using a predetermined condition, to thereby perform a route search.
Here, the cost check refers to checking a remaining capacity, a delayed time, a transfer distance, and the like of each link, and regarding the remaining capacity, a communication capacity obtained by adding a communication capacity corresponding to a header to a communication capacity requested by a user is calculated and the calculated communication capacity is compared to the remaining capacity, to thereby judge whether or not the condition is satisfied (Japanese Patent Application Laid-open No. 2008-301225).